Cave Spider Has Most Stretchable Silk

The egg sac silk of the cocoon stalk of the cave spider Meta menardi is the most stretchable egg sac silk yet tested, according to a study published Feb. 8 in the open access journal PLoS ONE.

Spider silk is of broad interest for its strength, extensibility and toughness and possible applications for material science and biomechanical engineering, and there are many different types of silk from many different spider species. In the current study, the authors, led by Nicola Pugno of Politecnico di Torino in Italy, collected egg sacs from caves in Piedmont in northwest Italy and tested their response to mechanical strain.

They found that the egg sac silk of the cocoon stalk was more stretchable than any previously tested egg sac silk. These results may partly reflect the fact that the silk was collected from its natural habitat rather than produced in a lab, the authors write.

“This observation paves the way for better understanding super-stretchable biological materials and also for a more rational design of the related bio-inspired nanomaterials”, says Dr. Pugno

Financial Disclosure: NMP is supported by ”Metrology on a Cellular and Macromolecular Scale for Regenerative Medicine” – Metregen (2009), supporting theoretical research for scaffold design. The research related to these results has received funding from the European Research Council under the European Union’s Seventh Framework Program (FP7/2007)/ERC Grant agreement nu [279985] (ERC StG Ideas Award to NMP on ”Bio-inspired hierarchical super nanomaterials”; the funding will officially start in 2012). MJB acknowledges support from an ONR-PECASE award (award number N00014-10-1-0562), no role in the results reported in this paper. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing Interest Statement: The authors have declared that no competing interests exist.